Currently,live streaming based on p2p or grid technology is very hot,some companys have obtained some VC investments.Some media companys ,such as News Group,BBC,have studied this technology and talk about some good or bad results from this technology.

P2p steaming is the latest generation of peer-to-peer technology,which evolved as a way to delivery live audio and video streaming over internet to **** users.Traditional solutions are client-server model ,all users get streaming content from central server,so many servers and much bandwidth are used up,no scalability,no robustness,overhead and too expensive.P2p live streaming solution solves these questions,uses existing desktop computing power and networking connectivity to transfer streaming contents to end users,very *****,one PC with a ADSL connection maybe broadcast DJ/VJ's voice/video to all over the world,for million users.(please see fig1)

Evolution of live streaming technology

The road of p2p live streaming technology include three kinds:Single-tree protocol,Multi-tree Delivery Protocols and Data-Driven Overlay Protocol.

The first applicative scenario in which the peer-to-peer approach to live media streaming was introduced is the large-scale broadcast distribution of non-interactive content: the most significant research papers date back to 2000, with the proposal of the Overcast and Scattercast architectures, which both employ a two-tiered infrastructure (the p2p part of the network is just the core, end-users don't take an active role in the content distribution) to spread the load from a single server to a large pool of supporting nodes.

The other field of interest, which was also explored around the year 2000, was small-scale, multiple source video distribution in cooperative environments with a certain aim at intra-company conferencing and media broadcasting: good results have been achieved by the Narada and Yoid research projects - the first has also been implemented as a commercial product for enterprise-wide brokering systems - which use a mesh-based infrastructure for keeping the global connectivity and managing the distribution trees which relay data streams.

In the following years (2001 to 2004), the research started focusing on completely distributed systems for media broadcast, and the three main branches of this field are fundamentally different in the way they approach the problem: many projects have studied methods which rely on single applicative multicast trees, like SpreadIt , PeerCast ,ESM and NICE , while others have explored approaches based on multiple trees - to obtain a better resiliency to node failures - and appropriate data encodings - to protect the playback quality in case of packet losses - like Splitstream , CoopNet and P2PCast finally, improvements with respect to the plain single-tree based solutions have been proposed with Zigzag and Bullet .

June ,2004,a HongKong student Zhang xin-yan and his partners published a paper "A Data-driven Overlay Network for Peer-to-Peer Live Media Streaming" and released coolstreaming software.From this time,many p2p live streaming system based this paper released ,such as pplive,ppstream,vatata,etc.please see fig2,this is a evolution of live streaming technology.

P2p live streaming system

Mostly p2p live streaming systems structure are like CDN,relay , proxy and delivery streaming contents to users' desktop PC.Users will also bear a responsibility as p2p streaming network node and make the grid network more stable and fluid,but CND nodes must be a server with much bandwidth,it's very expensive.

Now listing some p2p streaming systems,divide open source/freeware systems into commercial systems.

PeerCast.org was established in April 2002 as a non-profit site providing free P2P radio software. The aim of the project is to create an easy to use, simple and reliable software client that enables anyone to broadcast streaming media on the Internet without the need for expensive servers or bandwidth.Peercast maybe a oldest peer streaming opensource software.Now peercast have many fans using it for themself internet radio stations.If someone want to broadcast video contents,please visit http://www.scvi.net/ for more information.

FreeCast is a Java application which allows peer-to-peer streaming. It makes possible a stream broadcast to a large number of listeners from a simple DSL connection.FreeCast allows you to listen a live stream over Internet by using smartly resources. You can listen a webradio or share an event by allowing other listeners to make the same thing in the best conditions.Freecast is good start point for newbies studying peer streaming with java.

End System Multicast (ESM) was started in 1999 as an exploration into using overlay networks for an IP multicast service. It has since evolved into a system used for broadcasting high quality video streams to large numbers of recipients.This project is from CMU,some ideas for where ESM can be used include academic lectures, conferences, sporting events, Internet radio, religious services, graduation ceremonies, and music recitals.Now it is running very well in CMU school area network.

Vatata system is an end-to-end and large-scale solution for publishing , delivery and reception of streaming contents. This platform is an open system completely based on internet. Its grid and p2p technology guarantees the low-cost and clear delivery of content to millions of internet users. Any personal users or commercial users have full right to use Vatata for free.Vatata have relaesed broadcast server,client and tracker server,everyone can easily build their individual internet radio stations or TV stations through Vatata and the dreams of DJ and VJ will come true. Above version 1.5,Vatata begin to support broadcasting live streaming contents in LAN,self-orgernized p2p subnet in LAN. Vatata maybe a most user-friendly software among free p2p streaming systems.Vatata team called vatata --Poetic grid network of next-generation streaming media.If vatata open its source code from someday, it should be a next killer application like BitTorrent.

P2P-Radio is a program that can distribute audio and video streams (MP3/Ogg Vorbis/NSV) over the Internet in a peer-to-peer manner. It's possible to create your own internet radio station with P2P-Radio.

The NFT-TV system can utilize run-of-the-mill cable and DSL modem connections to support broadcasts of compressed video encoded at 320 by 240, 15 frames per second, streamed at a variety of bandwidths.

Using p2p live streaming technology will help two kinds companys' business. One is traditional media company,such as Cable-TV,satellite-TV,film company,Broadcast Radio,etc.These companys can use this technology delivery its multimedia contents to PC users through internet,develop a new market without much costs.Another companys are more important,these company maybe create a new kind entertainment market for billions internet user.This is really internet-TV,it's more interaction,more entertainment,and more global. These new players will grow fast,maybe take place of traditional media company. Of course,personal users can use p2p live streaming technology to setup yourself TV or Radio station,like own your blog space,this is new way to show yourself on internet.

P2p live streaming technology also brought bad news,copy rights are still a problem.Wall Street Journal said:"China has become the hotbed of a new technology that distributes live television signals over the Internet, exposing the world's pay-TV operators to the kind of online piracy that has plagued the music and movie businesses.",this report listed some Chinese p2p streaming companys,Roxbeam,PPlive,Sop,PPstream,etc.A German P2P system called Cyber***-TV, one of the first to use the technology, stopped distributing its streaming software after being slapped with a court injunction.

Conclusion

This's all,I use Vatata's poem as end of this article.

The horse passed west land
So build a village at the end of water
And make a camp fire
Begin to sing a drunken song.

Windows Movie Maker doesn't let me put videos from my digi cam because it's in the wrong format so what converter can I use?I want one that's pretty decent quality, doesn't cost anything, doesn't stick the logo on my videos and it converts all of the video, not just half of it.I used to have prism something but then my trial run ran out so yeah, I can't use that >.<And zamzar has a limit of 100MB :lHelp please?

A nice summary of P2P streaming technology. I just want to add one thing. The first P2P streaming concept was called "chaining." It was presented at the 1997 International Conference on Multimedia Computing and Systems by Prof. Kien Hua and his students at the University of Central Florida.

Hi,
This is a really nice summary, thanks for sharing! As you written in your list above, there are many streaming systems available for people to experience and opertae it by themselves.

Recently, I heard about another live streaming server DaCast, a cost-effective, self-service live streaming platform which integrate channel manager, monetization models and analytic dashboard in one platform. Even people with limited knowledge of live streaming can set up an account and manage streaming quickly and easily.